Generally, a cylinder deactivation (CDA) technology is applied to a vehicle engine to improve fuel efficiency thereof. When the engine operates in a CDA mode, fuel injection into some of cylinders provided in the engine stops, and thus, only the remaining cylinders are used to operate the engine.
The CDA technology is used during light-load operation of the vehicle, such as high-speed running, etc. Therefore, in comparison with a normal operating condition of the engine, in the CDA mode, fuel consumption decreases such that the fuel efficiency increases. However, the volume or pressure of exhaust gas decreases such that it is possible to have an effect on a driving condition of a turbocharger or on a re-circulated exhaust gas volume by an exhaust gas recirculation (EGR) system, etc. Therefore, it is important to boost an intake air pressure with the turbocharger, etc. normally, even though the engine operates in the CDA mode.
The foregoing is intended merely to aid in the understanding of the background of the present disclosure, and is not intended to mean that the present invention falls within the purview of the related art that is already known to those skilled in the art.